Seal for vapor devices.



P. H. THOMAS. SEAL FOR VAPOR DEVICES.

APPLICATION FILED JUNE 19,1905J Patented Feb. 27, 1912.

WITNESSES: 4/,,,, I

. UNITED STATES PATENT. OFFICE- M PERCY H. THOMAS, OF MONITCLAIR, NEW JERSEY, ASSIGNOR 1'0 COOPER HEWITT ELECTRIC COMPANY, OF NEW YORK, N. Y-, A CORPORATION OF NEW YORK.

Specification of Letters Patent.

Application filed June 19, 1905. Serial No. 265,889.

To all whom it may concern:

Be it known that I, PERCY H. THoMAs, a citizen of the United States, and resident of Montclair, county of Essex, State of New Jersey, have invented certain new and useful Improvements in Seals for Vapor Devices, of which the following is a specification.

The present invention relates .to means whereby a good and durable seal may be made in connection with vapor devices represented, for example, by mercury vapor converters or lamps. One of the diflicult problems connected with the sealing in of lead conductors in apparatus of this sort is that of permitting a large current to pass through the seal without heating the platinum sufliciently to cause it to expand sensibly more than the glass. To secure this result it is necessary first that the section of platinum carrying the current shall be large and that its length shall be small, furthermore it is desirable to have the quantity of platinum as small as possible for economical reasons. It is further very desirable in devices of this sort that the joint between the glass and the platinum which is exposed within the vacuum and which may be the starting point of a short circuit shall be as little affected by the heat from the seal which is carrying current as possible. These results are attained to a very large degree by the device shown in the figure which is one embodiment of my invention.

Another advantage attained from this form is extreme mechanical rigidity and small total dimensions of the platinum cup where inclosed by the glass. It further allows intimate contact between the leads in- I have shown th e details of only one of the electrodes and its connections, the corresponding electrode being substantially the same in construction.

In the drawing, 1 is the container of a mercury vapor apparatus, such as agconverter. This container is usually made of glass and is in the presentinstance assumed to be of that material. The negative electrode of the apparatus is shown at 2 as a mass or puddle of mercury and it is connected with the outside circuit by means of a lead-wire, 3, as shown.

. One of the positive electrodes is shown at 4, the same being made of iron, graphite, or

other suitable material, joined to an iron rod 5, having a screw-thread at each end, and connected on the one hand to the material of the electrode 4 and on the otherto the inside of a platinum sealing cup, 6. This cup 6 is sealed into the glass in the usual way and is spread on its inner side so that the heat radiating from the iron rod 5 shall exercise as little effect as possible upon the material of the platinum.

The cup 6 is made cylindricalat its upper end and provided externally with a screw thread with which engages an internal screw thread upon a copper connecting device, 7, which is joined to the externalcircuit by a lead-wire or conductor, 8. The

electrode 4 is supported within a receptacle,

or chamber, 9, having an opening at 10, on the side remote from the next adjacent receptacle or chamber, 11, which latter is proviled with an opening, 12, on its remote s1 e.

The object of the arrangement last described is that-of preventing short circuiting between the positive electrodes in the several chambers or receptacles.

It will be seen that the formation of the cup is made with a thin wall and that by providing such a cup with internal and external screw-threads and unitin it to the iron internal lead conductor an the external copper conductor by means of the said screw-threads, there is formed a very per- Patented Feb. 2'7, 1912.

feet and solid connection which provides practically direct electrical contact between the external and the internal conductors.

. Fig. 2 illustrates on a larger scale the cup and connections of Fig. 1. In this figure, 6,

is a cup of conducting material, which may be of platinum, formed with a cylindrical Y part and a flaring part and screw threads,

13, and 14; respectively on the outside and inside of the cylindrical partengaging with similar threads on the parts 7 and 5. When the parts 7 and 5 are properly screwed in position the friction between the threads threads, and the portion of the cup 6 which is sealed to the glass 15, 15-, thus relieving the latter of strains due to the expansion of the former. A great advantage results from this construction'in that current passes from 5 to 7 along the shortest dimension of the sheet of material forming the cup 6. It thus generates the least possible amount of heat.

The platinum cup shown enlarged in Fig. 2 has the flaring portion thinner than the body portion. In this figure it is shown tapering toward the outer edge. This form requires less material than the maintenance of the thickness of the body portion throughout and has other advantages. For example, the flexibility of the thinner material near the edge reduces the natural strain on the glass from expansion'and contraction.

I claim as my invention:

1. A 'seal for vapor devices or similar vacuum apparatus comprising as one element a glass container, the said seal con sisting of a' platinum cup sealed into the glass and connected with the internal device by means of a screw-threaded rod, the inner surface of the cup being flared away from the material of the rod.

2. A vapor device and -connections therefor comprising a container of glass, an electrode therein, a cup sealed into the glass and connected to the electrode by a suitable conductor, the cup extending outside the container and being cylindrical in form at that point and being externally screw threaded and joined to an external conductor by means of the said screw thread.

3. A vapor device and connections therefor, comprising a container of glass, an electrode therein, a cup sealed into the glass and connected to the electrode by a suitable conductor, the cup extending outside the contamer and being cylindrical in form at that point and being externally screw 55 thread coiiperating with an internal screw.

thread on said copper conductor.

4. In a vapor electric apparatus adapted to carry heavy currents and in which the container is made of glass or similar material, a thincup shaped connecting device, of platinum or similar metal, the same being provided with an internal and an-external screw-thread, one inside the container and the other outside the same, and coupling devices adapted to be joined to the said cup by means of the said screw-threads whereby a practically direct connection is made between the external and the internal circuit of the apparatus.

5. A wall of non-conducting material, a tubular support of conducting material sealed in an opening in said wall, and circuit terminals constructed frictionally'to enconnection respectively to the interior and exterior of said support.

7. A wall of non-conducting material, a tubular support of conducting. material sealed in an opening in said wall, and two circuit terminals constructed to be engaged frictionally respectively with the interior and exterior of said support. 7

8. A wall of non-conducting-material, a tubular support of conducting material formed with one closed end and having its open end sealed in an opening in said wall, and two circuit terminalsconstructed for detachable connection respectively to the interior and exterior of said support.

9. A closed receptacle of non-conducting material, a thimble of conducting material formed with one closed end protruding outside of said vessel and having its open end sealed in a wall of said vessel, a circuit ter minal within said vessel and a circuit terminal outside of said vessel, said terminals being constructed for detachable connection respectively to the'interior and exterior of said thimble.

10. A wall of non-conducting material, a tubular support of conducting material, having its end portion of thinner material than its body portion and having said end portion sealed in an opening in said wall, and separate circuit terminals respectively connected to the interior and exterior of said body portion of said support.

11. A wall of non-conducting material, a

tubular support having an end portion of larger diameter and of thinner material than its body portion, and having said end portion sealed in an opening in said Wall, 5 and separate circuit terminals respectively connected to the interior and exterior of said body portion of said support.

12. In combination with a Wall of nonc'onducting material, a thimble of metal 10 formed with a closed end and having its open end sealed in an opening in said Wall, the metal of said thimble being of reduced thickness at its open end Signed at New York, in the county of New York, and State of New York, this 1.5 15th day of June, A. D. 1905.

, PERCY H. THOMAS. Witnesses:

WM. H. CAPEL, V GEORGE H. STOCKBRIDGE. 

